High torque boring machine

ABSTRACT

A traveling support frame is mounted for up and down travel along upstanding guide columns. Drilling equipment is carried by the traveling frame. The drilling equipment includes a drive head and means coupling it to a rotary drive member in such a way that bending forces imposed on the drill stem are not transmitted by the drill head to such drive member.

rte States ate 1191 1111 3,736 %3 West 1 June S 1973 [54] HIGH TORQUE BORING MACHINE 2,863,638 12/1958 Thornburg 173/57 75 l t H ldl-LW t,S ttl,W h. l nvffn am es ea 6 as Primary Exammer-Ernest R. Purser Asslgneel The Robbins C(llnpany, Seattle Attorney-John O. Graybeal, George M. Cole and wash- Delbert J. Barnard [22] Filed: July 15, 1971 21 Appl. No; 162,843 [57] ABSTRACT A traveling support frame is mounted for up and down 521 U.S. c1 ..173/l63, 173/152 "ave! along upstanding guide Columns- Drilling equip 51 1m.c1. ..E21b 3/02 ment is carried y the traveling frame- The drilling 53 Field of Search ..173/57, 152, 163; equipment includes a drive head and means p g 175/85, 122, 170 it to a rotary drive member in such a way that bending forces imposed on the drill stem are not transmitted [56] References Cited by the drill head to such drive member.

UNITED STATES PATENTS 1,398,551 11 1921 Hanson ..173/57 x 7 Claims 4 Drawing Figures Patented June 5, 173' v 3,736,893

3 Sheets-Sheet 2 M VE/VTOAZ HAROLD WEST 44 //0//Z 721 I W. E' w WL! /ZZ ATTORNEYS Patented June 5, 1973 3,736,993

3 Sheets-Sheet 5 ATTORNEYS HIGH TORQUE BORING MACHINE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to earth boring or drilling machines. It particularly relates to means for isolating bending forces imposed on the drill stem from certain drive gearing.

2. Description of the Prior Art The present invention relates to an earth boring or drilling machine of the same basic type as disclosed in U.S. Pat. No. 3,220,494, granted on Nov. 30, l965 to Robert E. Cannon et al., in U.S. Pat. No. 3,454,l14, granted July 8, 1969 to Leland B. Poage, in U.S. Pat. No. 3,490,546, granted Jan. 20, 1970 to John S. Hattrup et al., in U.S. Pat. No. 3,463,247, granted Aug. 26, 1969 to Harold T. Klein, and in U.S. Pat. No. 3,554,298, granted Jan. 12, l97l to Harold T. Klein.

Like the machines disclosed by these patents the machine of the present invention is a precision earth drilling machine which includes rotary drilling equipment mounted for precision movement up and down along base supported guide column means by a traveling cross frame which is hydraulically raised and lowered.

The aforementioned U.S. Pat. No. 3,490,546 discloses a drill head which is constructed to include a universal joint, composed of mating spherical segments, for isolating bending forces imposed on the drill stem from a planetary form of speed reduction gearing. U.S. Pat. No. 2,972,388 discloses a two part drill head in which the two parts are connected together by a universal coupling of a knuckle joint type which also serves to isolate gearing from bending forces.

SUMMARY OF THE INVENTION Drilling machines according to the present invention comprise motor and gearing components for imparting rotation to a drill head. These components and the drill head are carried by a traveling cross frame which is mounted for precision movement up and down along upstanding guide columns, and is so moved by hydraulic thrust rams or linear motors, or the like.

According to the invention, the drilling equipment includes a bearing arrangement for the drill head which is designed to carry both axial and bending loads, and is adapted to isolate drive gearing for the drill head from bending forces which are developed in the drill pipe during certain phases of the drilling operation. Two axially spaced combination bearings (i.e., bearings which carry both axial and radial loads) support the drive head. These bearings both have spherically surfaced roller elements, the outer curvature of which falls on a common circle so that the drill head and the bearing races secured thereto can tilt about a center. The need for a pivot joint in addition to radial and thrust bearings is eliminated, resulting in a length saving at the drill head region. This length saving is benefited and is utilized in the machine of this invention.

BRIEF DESCRIPTION OF THE DRAWING In the drawing like letters and numerals refer to like parts, and:

FIG. 1 is an isometric view taken from above and looking towards one side and the front of a drilling machine constructed according to the present invention, showing the rotary drive apparatus in a partially raised position;

FIG. 2 is a view like FIG. 1, but showing the rotary drive apparatus in a lowered position;

FIG. 3 is a fragmentary front elevational view of the rotary drilling apparatus, partially in section; and

FIG. 4 is a fragmentary side elevational view taken through the drive head assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring more specifically to the several figures of the drawing, the illustrated embodiment is shown to comprise a lower or base frame assembly 10 including a base plate member 12 and a generally U-shaped (in plan) main frame 14 upstanding from the plate member 12. Frame 14 includes upstanding wall portions forming a pair of sockets 16 which occupy near corner positions on the plate member 12. The lower end portions of a pair of parallel guide columns 18 are received in the sockets 16 and are rigidly secured to the base frame member thereby. A fixed upper cross frame member 20 rigidly interconnects the upper ends of the guide columns 18. The base frame assembly 10 and the upper cross frame 20 together constitute main frame means in the illustrated embodiment.

The guide columns 18 support and guide a movable or traveling cross frame 22. Traveling cross frame 22 includes vertically spaced apart upper and lower guide sleeves 24, 26 which surroundingly engage the columns 18. A lower portion of the traveling cross frame 22 extends laterally from the sleeves 26 into a position over the base frame assembly 10. It includes wall means 28 forming a housing for a bearing assembly (FIG. 4). A second housing 30 extends laterally from the upper guide sleeves 26 into a position above the housing 28. Housings 28, 30, sleeves 24, 26 and the interconnecting parts of traveling cross frame 22 are structurally integrated into a single rigid frame assembly.

The upper housing 30 contains collector gearing 32 (FIG. 3) having a pair of input gears 34 and asingle output gear 36.

A pair of drive motor assemblies are bolted to the housing 30 and each has an output shaft which is coupled to one of the inner gears 34, as will hereinafter be explained in greater detail.

In preferred form the motor assemblies comprise an electric motor 38 and a planetary type reduction transmission 40, such as the type shown by FIG. '7 of the aforementioned U.S. Pat. No. 3,454,114.

Traveling cross frame 22 is raised and lowered by a plurality of thrust rams 41. According to the invention, each thrust ram 41 comprises a hollow piston chamber or cylinder designated 42, and a piston comprising a rod 44 and a head 45. In the illustrated embodiment the closed ends of the piston housings 42 are directed upwardly and the open ends are directed downwardly. Mounting sockets 46 of split form receive the lower end portions of the housings 42 and firmly secure them to the traveling cross frame 22 (FIG. 3). Piston rods 44 include lower end mounting portions 48 which are secured to the lower frame 10. The mounting portions 48 are received between vertical plate portions of the frame member 14 and are secured to such plate portions by transverse mounting pins 56. The thrust rams 41 are essentially identical to the thrust rams shown by the aforementioned U.S. Pat. No. 3,454,114. Accordingly, further details of these thrust rams 41, including the means for supplying and exhausting a motive fluid to and from them, will not be specifically described herein. Rather, reference is made to U.S. Pat. No. 3,454,l 14, the contents of which are expressly incorporated herein by this reference.

As best shown by FIGS. 1 and 2, the guide columns 18 and two of the thrust rams 41 are spaced apart in a quadrangular pattern, with the guide columns 18 being relatively close to comer portions of the base frame assembly on one side of such base frame 10 and the two thrust rams 41 being in the corner portions on the other side of base frame assembly 10. The third thrust ram 41 is located generally between the guide columns 18 and forms a triangular pattern with the other two thrust rams 41. The drilling axis is located substantially at the center of forces within the triangle. The upper ends of the cylinders 42 are interconnected by a generally triangular shaped traveling head frame 52.

Herein the term jack means is sometimes used to describe the thrust ram assemblies 41. Indeed, the double acting linear hydraulic motors 41 are a type of jack means. It is recognized that the jack means could possibly take other forms in other installations (e.g., as a mechanical screw).

Reference is now made to FIG. 3 of the drawing. In this figure, and in other figures as well, the motor is designated 38 and the speed reduction gearing is generally designated 40. Each motor-gear reduction assembly 38, 40 is in the form of an elongated vertical column which is substantially parallel to the guide columns 18 and the thrust rams 41.

The lower portion of each transmission main shaft 54 is spline connected at 56 to a tubular extension 58. A combined bearing 60 is located within the lower portion 62 of drive box 64 in surrounding relationship to the upper end of the tubular extension 58. An annular retaining flange 66, connected to the drive box member 62 by a plurality of machine bolts (not shown) serves to hold the bearing 60 in place.

The extension 58 is located within a housing part which is bolted at its upper end to the gear box part 62 and at its lower end to the collector gearing housing 30. The bolts securing the housing part 68 to housing 30 are designated 70 in FIGS. 1 and 2. In the same figures the bolts which secure the lower mounting flange of the housing 30 to the housing 28 are designated 72.

Referring specifically to FIG. 3, the extension 58 includes internal axial splines which mate with external splines on the upper end portion of a shaft 74 which mounts pinion gears 34 for rotation. Each gear member 34 is annular in form and is spline connected to the shaft 74. The upper end of each shaft 74 is contained within a combination bearing unit 76 and the lower end portion of each shaft 74 is contained within a similar lower combination bearing 78.

Upper and lower combination bearings 80, 82 serve to mount a central shaft 84 to which the gear 36 is secured, such as by splines. The lower end portion of shaft 84 extends through a bottom opening in housing 30 and downwardly below such housing 30 and includes external splines 86. The splined lower end portion of shaft 84 extends into an upstanding tubular drive member 86 (FIG. 4). This drive member 86 includes an enlarged diameter lower end portion 88 which carries peripheral splines 90. This splined lower end portion 88 of member 86 is contained within a larger diameter tubular drive member 92. Drive member 92 is shown to be of composite construction, and

to comprise upper and lower parts, each of which includes a reduced diameter end portion. The upper end portion of the upper part of member 92 is contained within a combination bearing 94. The lower end portion of the lower part of member 162 is contained within a larger combination bearing 96. Asocket 98 is formed in the lower portion of housing 28 to receive the bearing 96. Bearing 94 is supported on a shoulder 100 formed at the upper end of member 92, and is radi ally outwardly bounded by an annular member 102. An annular disc like seal member 104 is secured between the upper surface of bearing 94 and an annular retaining flange 106 which is secured to member 102 by bolts 108. The seal member 106 makes loose contact with the upper end portion of drive member 86 so that relative movement can occur between the two. A main drive head 110 extends axially through the tubular lower portion 112 of drive member 92. Drive head 110 includes an enlarged diameter upper end portion 114 on the outer periphery of which are formed axial splines 116. The splines 116 mate with a set of longer axial splines 118 formed on the inside wall of the intermediate drive member 92. The splines 116, 118 couple the drive head 110 and the drive member 92 together for conjoint rotation, but permit a limited amount of axial movement of the drive head 110 relative to the drive member 92.

The lower end portion of the drill head 110 includes a tool joint component, shown in the form of an interiorly threaded socket or box 120. A complementary pin type tool joint component 121 of an upper section of drill pipe 122 is thread connected to the tool joint component 120. A tubular center shaft 124 extends from a lower portion of drive head 110, upwardly through the hollow interior of drive head 110, then through the hollow interior of drive member 86, then through the hollow interior of gear shaft 84, and then upwardly through space to a connection with the lower portion of a fluid transmitting swivel coupler (not shown) positioned below top frame member 52. The upper portion of the fluid coupler is connected to a source of drilling fluid which is delivered downwardly through the coupler and the tubular shaft 124 to the hollow interior of the drill pipe. The upper portion of the swivel coupler 126 is also connected to a piston rod (not shown) which projects upwardly into a cylinder 128 (FIGS. 1 and 2) located on top of frame member 52. The cylinder 128 is a part of a double acting linear hydraulic motor provided for balancing the weight of the drill stem and the drive head 110. This balancing feature is covered in detail in a copending application Ser. No. 75,020, filed Sept. 24, 1970, entitled Earth Drilling Machine and now U.S. Pat. No. 3,695,364, and as signed to the assignee of this application.

Referring specifically to FIG. 4, the combination bearings 94, 96 contain tapered roller elements 130, 132, respectively. The elements 130, 132 are longitudinally curved. The curvature is the same for all elements 130, 132 and falls on an imaginary circle having its center approximately at 134. Owing to this arrangement, at least the major bending forces transmitted to drive head 110 by the drill stern are not transmitted up to the central drive gear 36. Instead, the bending forces merely cause the drive head 110 and the drive member 92, to which it is spline connected, to rotate sideways slightly about the center 124. The splines 90 are short enough and enough clearance exists where they mate with splines 91 so that the drive member 86 tilts very little or not at all upon tilting movement of drive head 110 in drive member 92. Thus, in effect a hinge joint exists between drive members 88, 92 which is incapable of transmitting bending forces.

A flexible wall seal member 126 is secured to a lower portion of the traveling cross frame 22, such as by a plurality of bolts 128, and is also secured to an annular sleeve 130 which surrounds the lower portion 112 of drive member 92. I

It is to be understood that in most respects the illustrated embodiment is merely one example of many possible hardware forms of the invention, and it is'the following claims rather than the drawing and description relating thereto which are to be used for defining and limiting the invention.

What is claimed is:

1. In a drilling mechanism comprising upstanding guide column means, traveling cross frame means mounted for precision up and down travel along said column means, and drilling equipment carried by said traveling cross frame means and including a rotary drill head connectible to drill pipe, motor means and drive transmission means drivingly connecting said motor means to said drill head, the improvement characterized by:

said drill head comprising means mounting it on the traveling cross frame means, including bearing means for carrying both axial and radial loads, said bearing means also serving to mount the drive head for limited pivotal movement relative to said traveling cross frame means so that the drive head can tilt sideways in response to bending forces imposed by the drill pipe;

said drive transmission means including a drive member, and means interconnecting said drive member and said drill head for rotary motion transmission from the former to the latter, said means being capable of transmitting very little or none of the sideways tilting movement of the drill head to said drive member.

2. The drilling mechanism improvement of claim 1, wherein said bearing means comprises vertically spaced apart upper and lower bearing assemblies, each having fixed and rotatable bearing races, said bearing races having spherically curved race surfaces with one race surface of each bearing facing inwardly towards a center of curvature which is substantially common with the inwardly facing race of the other bearing, with said bearing races serving to mount the drive head for limited pivotal movement substantially about said center of curvature.

3. The drilling mechanism improvement of claim 2, further comprising a plurality of roller elements between said races, said roller elements being longitudinally curved, and of a curvature and attitude to mate with said race surfaces.

4. The drilling mechanism improvement of claim 1, wherein said drill head includes an outer portion supported by said bearing means and an inner portion mounted for limited axial movement relative to said outer portion but coupled thereto for conjoint rotation therewith, said inner portion carrying a tool joint component connectible to a complementary tool joint component on a drill pipe member.

5. The drilling mechanism improvement of claim 4, wherein said drive member includes a portion which projects into the outer portion of said drive head, and

connection means between said drive member portion and said drive head outer portion serving to couple them together for conjoint rotation, but permitting said drive head outer member to tilt relative to said drive member portion.

6. The drilling mechanism improvement of claim 5, wherein said bearing means comprises vertically spaced apart upper and lower bearing assemblies, each having fixed and rotatable bearing races, said bearing races having spherically curved race surfaces with one race surface of each bearing facing inwardly towards a center of curvature which is substantially common with the inwardly facing race of the other bearing, with said bearing races serving to mount the drive head for limited pivotal movement substantially about said center of curvature.

7. The drilling mechanism improvement of claim 6, further comprising a plurality of roller elements between said races, said roller elements being longitudinally curved, and of a curvature and attitude to mate with said race surfaces.

* II! i 

1. In a drilling mechanism comprising upstanding guide column means, traveling cross frame means mounted for precision up and down travel along said column means, and drilling equipment carried by said traveling cross frame means and including a rotary drill head connectible to drill pipe, motor means and drive transmission means drivingly connecting said motor means to said drill head, the improvement characterized by: said drill head comprising means mounting it on the traveling cross frame means, including bearing means for carrying both axial and radial loads, said bearing means also serving tO mount the drive head for limited pivotal movement relative to said traveling cross frame means so that the drive head can tilt sideways in response to bending forces imposed by the drill pipe; said drive transmission means including a drive member, and means interconnecting said drive member and said drill head for rotary motion transmission from the former to the latter, said means being capable of transmitting very little or none of the sideways tilting movement of the drill head to said drive member.
 2. The drilling mechanism improvement of claim 1, wherein said bearing means comprises vertically spaced apart upper and lower bearing assemblies, each having fixed and rotatable bearing races, said bearing races having spherically curved race surfaces with one race surface of each bearing facing inwardly towards a center of curvature which is substantially common with the inwardly facing race of the other bearing, with said bearing races serving to mount the drive head for limited pivotal movement substantially about said center of curvature.
 3. The drilling mechanism improvement of claim 2, further comprising a plurality of roller elements between said races, said roller elements being longitudinally curved, and of a curvature and attitude to mate with said race surfaces.
 4. The drilling mechanism improvement of claim 1, wherein said drill head includes an outer portion supported by said bearing means and an inner portion mounted for limited axial movement relative to said outer portion but coupled thereto for conjoint rotation therewith, said inner portion carrying a tool joint component connectible to a complementary tool joint component on a drill pipe member.
 5. The drilling mechanism improvement of claim 4, wherein said drive member includes a portion which projects into the outer portion of said drive head, and connection means between said drive member portion and said drive head outer portion serving to couple them together for conjoint rotation, but permitting said drive head outer member to tilt relative to said drive member portion.
 6. The drilling mechanism improvement of claim 5, wherein said bearing means comprises vertically spaced apart upper and lower bearing assemblies, each having fixed and rotatable bearing races, said bearing races having spherically curved race surfaces with one race surface of each bearing facing inwardly towards a center of curvature which is substantially common with the inwardly facing race of the other bearing, with said bearing races serving to mount the drive head for limited pivotal movement substantially about said center of curvature.
 7. The drilling mechanism improvement of claim 6, further comprising a plurality of roller elements between said races, said roller elements being longitudinally curved, and of a curvature and attitude to mate with said race surfaces. 